Preheat oven to 200C. Place beetroot in an oven proof dish with a lid. Drizzle with olive oil, a good sprinkle of salt and rosemary. Bake until tender- about 1 hour.
Once the beetroots have cooked, cool until you can handle them. Peel off skins and discard.
Bring a 5L pot of water to the boil. Once you’ve reached boiling, add 1 tsp salt and pasta. Cook as per packet instructions.
While the pasta cooks add peeled beetroot, feta, garlic, vinegar, olive oil, pepper, ⅓ tsp salt, dill, zest from ½ lemon, juice from the whole lemon and pine nuts/seeds to a blender. Blend until smooth, adding a few Tbsp water as needed. Taste the sauce- add more lemon or salt if desired.
Drain pasta, reserving approx 1 tablespoon of the pasta water. Pour beetroot sauce into the pasta with reserved water, and mix to combine.
Serve immediately topped with crumbled feta, walnuts and seasoning.
